linux-toradex.git/include/target/target_core_backend.h, branch v3.14.4

target/sbc: Add DIF TYPE1+TYPE3 read/write verify emulation

2014-01-18T09:53:12+00:00

This patch adds support for DIF read/write verify emulation
for TARGET_DIF_TYPE1_PROT + TARGET_DIF_TYPE3_PROT operation.

This includes sbc_dif_verify_write() + sbc_dif_verify_read()
calls accessable by backend drivers to perform DIF verify
for SGL based data and protection information.

Also included is sbc_dif_copy_prot() logic to copy protection
information to/from backend provided protection SGLs.

Based on scsi_debug.c DIF TYPE1+TYPE3 emulation.

v2 changes:
  - Select CRC_T10DIF for TARGET_CORE in Kconfig (Fengguang)
  - Drop IP checksum logic from sbc_dif_v1_verify (MKP)
  - Fix offset on app_tag = 0xffff in sbc_dif_verify_read()

Cc: Martin K. Petersen 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Sagi Grimberg 
Cc: Or Gerlitz 
Signed-off-by: Nicholas Bellinger

target: Add DIF related base definitions

2014-01-18T09:52:34+00:00

This patch adds DIF related definitions to target_core_base.h
that includes enums for target_prot_op + target_prot_type +
target_prot_version + target_guard_type + target_pi_error.

Also included is struct se_dif_v1_tuple, along with changes
to struct se_cmd, struct se_dev_attrib, and struct se_device.

Also, add new se_subsystem_api->[init,format,free]_prot() callers
used by target core code to setup backend specific protection
information after the device has been configured.

Enums taken from Sagi Grimberg's original patch.

v2 changes:
  - Drop guard_type related definitions
  - Update target_prot_op + target_prot_ho definitions (Sagi)
  - Drop SCF_PROT + pi_prot_version flag
  - Add se_subsystem_api->format_prot() (Sagi)
  - Add hw_pi_prot_type device attribute

Cc: Martin K. Petersen 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Sagi Grimberg 
Cc: Or Gerlitz 
Signed-off-by: Nicholas Bellinger

target: Pass through I/O topology for block backstores

2013-11-12T21:44:54+00:00

In addition to block size (already implemented), passing through
alignment offset, logical-to-phys block exponent, I/O granularity and
optimal I/O length will allow initiators to properly handle layout on
LUNs with 4K block sizes.

Tested with various weird values via scsi_debug module.

One thing to look at with this patch is the new block limits values --
instead of granularity 1 optimal 8192, Lio will now be returning whatever
the block device says, which may affect performance.

Signed-off-by: Andy Grover 
Acked-by: Martin K. Petersen 
Signed-off-by: Nicholas Bellinger

target: Make helpers non static for EXTENDED_COPY command setup

2013-09-10T23:48:39+00:00

Both target_alloc_sgl() and transport_generic_map_mem_to_cmd() are
required by EXTENDED_COPY logic when setting up internally dispatched
command descriptors, so go ahead and make both of these non static.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: Roland Dreier 
Cc: Zach Brown 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Allow sbc_ops->execute_rw() to accept SGLs + data_direction

2013-09-09T21:29:28+00:00

COMPARE_AND_WRITE expects to be able to send down a DMA_FROM_DEVICE
to obtain the necessary READ payload for comparision against the
first half of the WRITE payload containing the verify user data.

Currently virtual backends expect to internally reference SGLs,
SGL nents, and data_direction, so change IBLOCK, FILEIO and RD
sbc_ops->execute_rw() to accept this values as function parameters.

Also add default sbc_execute_rw() handler for the typical case for
cmd->execute_rw() submission using cmd->t_data_sg, cmd->t_data_nents,
and cmd->data_direction).

v2 Changes:
  - Add SCF_COMPARE_AND_WRITE command flag
  - Use sbc_execute_rw() for normal cmd->execute_rw() submission
    with expected se_cmd members.

Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Martin Petersen 
Cc: Chris Mason 
Cc: James Bottomley 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Add sbc_execute_unmap() helper

2013-04-25T08:05:24+00:00

iblock_execute_unmap() and fd_execute_unmap share a lot of code.
Add sbc_execute_unmap() helper to remove duplicated code for
iblock_execute_unmap() and fd_execute_unmap().

Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Cc: Nicholas Bellinger 
Signed-off-by: Asias He 
Signed-off-by: Nicholas Bellinger

target: Rename spc_get_write_same_sectors -> sbc_get_write_same_sectors

2013-02-23T20:46:14+00:00

Trivial, but WRITE SAME is an SBC command so it seems strange for a
related function (defined in target_core_sbc.c) to be in the spc_
namespace.

Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status

2013-02-13T19:27:51+00:00

This patch allows IBLOCK to check block hints in request_queue->flush_flags
when reporting current backend device WriteCacheEnabled status to a remote
SCSI initiator port.

This is done via a se_subsystem_api->get_write_cache() call instead of a
backend se_device creation time flag, as we expect REQ_FLUSH bits to possibly
change from an underlying blk_queue_flush() by the SCSI disk driver, or
internal raw struct block_device driver usage.

Also go ahead and update iblock_execute_rw() bio I/O path code to use
REQ_FLUSH + REQ_FUA hints when determining WRITE_FUA usage, and make SPC
emulation code use a spc_check_dev_wce() helper to handle both types of
cases for virtual backend subsystem drivers.

(asias: Drop unnecessary comparsion operators)

Reported-by: majianpeng 
Cc: majianpeng 
Cc: Christoph Hellwig 
Cc: Jens Axboe 
Cc: James Bottomley 
Signed-off-by: Nicholas Bellinger

target: Export SPC inquiry emulation

2013-02-13T19:27:22+00:00

Some target drivers might need to access the inquiry data
directly, without sending out the actual command.
So export these functions.

Signed-off-by: Hannes Reinecke 
Cc: Nicholas Bellinger 
Signed-off-by: Nicholas Bellinger

target: Make spc_get_write_same_sectors return sector_t

2012-11-28T06:49:25+00:00

We already expect TFO->get_blocks() to return sector_t for zero value case
when doing WRITE_SAME to the end of the backend device, so go ahead and return
sector_t from spc_get_write_same_sectors() to handle this case properly.

Also, update the single iblock_execute_write_same() caller of this code.

Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Signed-off-by: Nicholas Bellinger